Effects of growth and annealing temperatures on the structural and the optical properties of In0.6Al0.4As/Al0.4Ga0.6As quantum dots

In0.Al0.4As/Al0.4Ga0.6As quantum dots (QDs) were grown on GaAs (001) substrates by using molecular beam epitaxy utilizing a modified Stranski-Krastanow method. Atomic force microscopy images showed that the size of the In0.6Al0.4As QDs increased with increasing growth temperature. Photoluminescence spectra at 300 K showed that the exciton peaks corresponding to the interband transitions from the ground electronic subband to the ground heavy-hole subband (E1-HH1) of the In0.6Al0.4As/Al0.4Ga0.6As QDs shifted to large energy side with increasing growth temperature resulting from an increase in the height of the In0.6Al0.4As QDs. While the (E1-HH1) peak position of the PL spectra shifted toward larger energy side with increasing up to an annealing temperature of 700 °C, it shifted toward lower energy above 700 °C. The structural and the optical properties of In0.6Al0.4As/Al0.4Ga0.6As QDs were affected by the growth and annealing temperatures.

Estimation of size of cord blood inventory based on high-resolution typing of HLAs

Methods for estimating the cord blood (CB) inventory size required vary according to the ethnic diversity of the HLA, degree of HLA matching and HLA-typing resolution. We estimated the CB inventory size required using 7190 stored CB units (CBU) and 2450 patients who were awaiting or underwent allogeneic hematopoietic stem cell transplantation. With high-resolution typing of HLA-A, B and DRB1, 94.6% of Korean patients could find CBUs in 100 000 CBUs with a 5/6 match, and 95.7% could find CBUs in 5000 CBUs with a 4/6 match. With low-resolution typing of HLA-A and B and high-resolution typing of leukocyte antigen-DRB1, 95% of patients could find CBUs in 50 000 CBUs with a 5/6 match, and 96.7% could find CBUs in 3000 CBUs  with a 4/6 match. With additional high-resolution typing for HLA-A and B, which could improve transplantation outcome, the size of the CB inventory would need to increase twofold for Koreans.

Comparison of the effects of normal saline versus Plasmalyte on acid-base balance during living donor kidney transplantation using the Stewart and base excess methods

BACKGROUND

Ischemia-reperfusion injury is an inevitable consequence of kidney transplantation, leading to metabolic acidosis. This study compared the effects of normal saline (NS) and Plasmalyte on acid-base balance and electrolytes during living donor kidney transplantation using the Stewart and base excess (BE) methods.

METHODS

Patients were randomized to an NS group (n = 30) or a Plasmalyte group (n = 30). Arterial blood samples were collected for acid-base analysis after induction of anesthesia (T0), prior to clamping the iliac vein (T1), 10 minutes after reperfusion of the donated kidney (T2), and at the end of surgery (T3). In addition serum creatinine and 24-hour urine output were recorded on postoperative days 1,2, and 7. Over the first postoperative 7 days we recorded episodes of graft failure requiring dialysis.

RESULTS

Compared with the Plasmalyte group, the NS group showed significantly lower values of pH, BE, and effective strong ion differences during the postreperfusion period (T2 and T3). Chloride-related values (chloride [Cl(-)], free-water corrected Cl(-), BEcl) were significantly higher at T1, T2, and T3, indicating hyperchloremic rather than dilutional metabolic acidosis. Early postoperative graft functions in terms of serum creatinine, urine output, and graft failure requiring dialysis were not significantly different between the groups.

CONCLUSIONS

Both NS and Plamalyte can be used safely during uncomplicated living donor kidney transplantation. However, Plasmalyte more stably maintains acid-base and electrolyte balance compared with NS especially during the postreperfusion period.

Long-term metformin use reduces gastric cancer risk in type 2 diabetics without insulin treatment: a nationwide cohort study

BACKGROUND

Metformin use has been associated with a decreased incidence and mortality of various cancers.

AIM

To evaluate the association between metformin use and gastric cancer.

METHODS

We randomly selected 100 000 type 2 diabetic patients from the 2004 Korean National Health Insurance claim database, and assessed gastric cancer incidence among 39 989 patients (aged 30-97 years) who were regularly treated with anti-diabetic drugs and followed-up from 2004 to 2010. In total, 26 690 patients had used metformin out of 32 978 diabetics who had not regularly used insulin (insulin non-users), and 5855 patients had used metformin out of 7011 regular insulin users.

RESULTS

Patients who used metformin showed a lower incidence of gastric cancer than those who did not use metformin, in insulin non-users (P = 0.047, log-rank test). However, in patients on regular insulin, there was no difference of gastric cancer incidence according to metformin use. In insulin non-users, the adjusted hazard ratio (AHR) for metformin use was 0.73 (95% confidential interval [CI], 0.53-1.01) with borderline statistical significance (P = 0.059). Duration of metformin use was associated with the reduction in gastric cancer risk (AHR, 0.88; 95% CI 0.81-0.96, P = 0.003), especially in patients who used metformin for more than 3 years (AHR, 0.57; 95% CI, 0.37-0.87; P = 0.009).

CONCLUSION

Metformin use >3 years in type 2 diabetics who do not use insulin is associated with a significantly reduced gastric cancer risk.

Phospho-Rb (Ser780) as a biomarker in patients with cervical lymph node metastases from an unknown primary tumour: a retrospective cohort study

OBJECTIVES

Cervical lymph node metastases from an unknown primary tumour are a heterogeneous disease entity with various clinical features. There are many controversies regarding treatment methods and treatment response predictions. Therefore, we examined the prognostic significance of biomarkers in patients with cervical metastasis of unknown primary tumour.

DESIGN

A molecular study of retrospective cohorts.

SETTING

University teaching hospital.

MAIN OUTCOME MEASURES

Metastatic cervical lymph nodes of 36 patients with cervical unknown primary metastasis of squamous cell carcinoma were assessed by in situ hybridisation for human papillomavirus and immunohistochemistry for p16, retinoblastoma protein (phospho-Ser780), hypoxia-inducible factor-1α, glucose transporter 1 and carbonic anhydrase 9 expression. Clinicopathological factors and biomarkers were analysed for their associations with disease-free survival and overall survival.

RESULTS

Univariate analysis showed that nodal extracapsular spread was associated with poor overall survival (P = 0.049), nodal-positive retinoblastoma protein staining were significantly associated with poor outcomes of both disease-free survival (P = 0.035) and overall survival (P = 0.019), Multivariate analysis revealed that nodal positivity of retinoblastoma protein and nodal extracapsular spread were the significant predictors of overall survival (P = 0.049, hazard ratio = 6.21, 95% confidence interval = 1.01-38.35 and P = 0.037, hazard ratio = 4.34, 95% confidence interval = 1.09-17.21, respectively).

CONCLUSION

The retinoblastoma protein expression of metastatic lymph nodes represents an independent prognostic indicator in patients with cervical metastasis of unknown primary tumour.

Postoperative hypoalbuminemia as a risk factor for surgical site infection after oral cancer surgery

OBJECTIVES

Postoperative surgical site infection (SSI) is a frequent postoperative complication in patients with oral cancer and significantly affects patient recovery and medical expenses. The aim of this study was to examine the predictors of SSI in patients undergoing major surgery for oral or oropharyngeal squamous cell carcinoma (OSCC) and to determine the relationship between perioperative albumin and the development of SSI.

SUBJECTS AND METHODS

In 337 consecutive patients who underwent clean-contaminated surgery for OSCC, serum albumin, glucose, and hemoglobin levels were perioperatively measured. Differences between the groups were examined using Fisher's exact test, Mann-Whitney U-test, and multiple logistic regression analysis.

RESULTS

Surgical site infection was detected in 88 (26.1%) patients with median time to development of 10 (2-25) days. Multiple logistic regression analysis showed that only postoperative serum albumin < 2.5 g dl(-1) was an independent variable predictive of SSI (P = 0.003). The duration of hospital stay was negatively correlated with postoperative albumin (R(2) = -0.302, P < 0.001).

CONCLUSION

Early postoperative hypoalbuminemia <2.5 g dl(-1) is an independent risk factor for the development of SSI in patients undergoing oral cancer surgery. Clinicians should be aware of the implications of postoperative hypoalbuminemia and consider more intensive postoperative care in these patients.

Noncancer health events as a leading cause of competing mortality in advanced head and neck cancer

BACKGROUND

The survival of patients with head and neck squamous cell carcinoma (HNSCC) can be affected by noncancer health events (NCHE) as well as by index cancer progression and second primary cancer (SPC). This study aimed to investigate the risk factors for NCHE and noncancer mortality (NCM) in patients with advanced-stage HNSCC.

PATIENTS AND METHODS

This cohort study involved 600 consecutive patients with overall stage III to IV HNSCC who were treated between 2001 and 2010 at our tertiary referral hospital. NCHE was defined as re-admission (i.e. after the primary treatments for the index tumors) due to noncancer-related causes. The incidences of NCHE and NCM and their risk factors were analyzed by using cumulative incidence and cause-specific hazard functions.

RESULTS

During a median follow-up period of 54 months, 224 (37.3%) and 55 (9.2%) of the 600 patients had NCHE and NCM, respectively. The 5-year index cancer mortality, SPC mortality, and NCM rates were 23.8%, 4.2%, and 8.9%, respectively. Multivariate analyses revealed that body mass index <20 kg/m(2) (P = 0.018), Charlson comorbidity index (CCI) ≥1 (P < 0.001), tumor recurrence (P < 0.001), SPC occurrence (P < 0.001), and initial chemotherapy (P = 0.049) were independent NCHE predictors. Older age (P < 0.001), CCI ≥1 (P = 0.008), tumor recurrence (P < 0.001), and SPC occurrence (P = 0.047) were independent NCM predictors. Patients with respiratory NCHE were at a higher risk of NCM than patients with other NCHE types (P < 0.001).

CONCLUSIONS

One or more comorbidities, tumor recurrence, and SPC occurrence were independent predictors of both NCHE and NCM. Patients with respiratory NCHE had a particularly high risk of NCM.

Inhibition of cyclophilin D by cyclosporin A promotes retinal ganglion cell survival by preventing mitochondrial alteration in ischemic injury

Cyclosporin A (CsA) inhibits the opening of the mitochondrial permeability transition pore (MPTP) by interacting with cyclophilin D (CypD) and ameliorates neuronal cell death in the central nervous system against ischemic injury. However, the molecular mechanisms underlying CypD/MPTP opening-mediated cell death in ischemic retinal injury induced by acute intraocular pressure (IOP) elevation remain unknown. We observed the first direct evidence that acute IOP elevation significantly upregulated CypD protein expression in ischemic retina at 12 h. However, CsA prevented the upregulation of CypD protein expression and promoted retinal ganglion cell (RGC) survival against ischemic injury. Moreover, CsA blocked apoptotic cell death by decreasing cleaved caspase-3 protein expression in ischemic retina. Of interest, although the expression level of Bcl-xL protein did not show a significant change in ischemic retina treated with vehicle or CsA at 12 h, ischemic damage induced the reduction of Bcl-xL immunoreactivity in RGCs. More importantly, CsA preserved Bcl-xL immunoreactivity in RGCs of ischemic retina. In parallel, acute IOP elevation significantly increased phosphorylated Bad (pBad) at Ser112 protein expression in ischemic retina at 12 h. However, CsA significantly preserved pBad protein expression in ischemic retina. Finally, acute IOP elevation significantly increased mitochondrial transcription factor A (Tfam) protein expression in ischemic retina at 12 h. However, CsA significantly preserved Tfam protein expression in ischemic retina. Studies on mitochondrial DNA (mtDNA) content in ischemic retina showed that there were no statistically significant differences in mtDNA content among control and ischemic groups treated with vehicle or CsA. Therefore, these results provide evidence that the activation of CypD-mediated MPTP opening is associated with the apoptotic pathway and the mitochondrial alteration in RGC death of ischemic retinal injury. On the basis of these observations, our findings suggest that CsA-mediated CypD inhibition may provide a promising therapeutic potential for protecting RGCs against ischemic injury-mediated mitochondrial dysfunction.

Unusual maternal uniparental isodisomic x chromosome mosaicism with asymmetric y chromosomal rearrangement

Infertile men with azoospermia commonly have associated microdeletions in the azoospermia factor (AZF) region of the Y chromosome, sex chromosome mosaicism, or sex chromosome rearrangements. In this study, we describe an unusual 46,XX and 45,X mosaicism with a rare Y chromosome rearrangement in a phenotypically normal male patient. The patient's karyotype was 46,XX[50]/45,X[25]/46,X,der(Y)(pter→q11.222::p11.2→pter)[25]. The derivative Y chromosome had a deletion at Yq11.222 and was duplicated at Yp11.2. Two copies of the SRY gene were confirmed by fluorescence in situ hybridization analysis, and complete deletion of the AZFb and AZFc regions was shown by multiplex-PCR for microdeletion analysis. Both X chromosomes of the predominant mosaic cell line (46,XX) were isodisomic and derived from the maternal gamete, as determined by examination of short tandem repeat markers. We postulate that the derivative Y chromosome might have been generated during paternal meiosis or early embryogenesis. Also, we suggest that the very rare mosaicism of isodisomic X chromosomes might be formed during maternal meiosis II or during postzygotic division derived from the 46,X,der(Y)/ 45,X lineage because of the instability of the derivative Y chromosome. To our knowledge, this is the first confirmatory study to verify the origin of a sex chromosome mosaicism with a Y chromosome rearrangement.

Attitudinal concordance toward uptake and disclosure of genetic testing for cancer susceptibility in patient-family member dyads

Decisions for cancer susceptibility genetic testing (CSGT) uptake and dissemination of results occur within the family context. A national survey was performed with 990 patient-family member dyads (participation rate:76.2%), with paired questionnaires examining attitudes toward CSGT uptake and disclosure of results in response to a hypothetical scenario in which a reliable CSGT was available for the specific cancer a patient was being treated. While most patients and family members responded they would uptake or recommend CSGT if available, concordance between the dyads was poor for both patient's testing (agreement rate 77.5%, weighted κ=0.09) and first-degree relatives' testing(agreement rate 78.0%, weighted κ=0.09). Most patients (93.2%) and family members (92.9%) indicated that patients should disclose positive CSGT results to family members, with dyadic agreement of 89.1% (κ=0.15). However, there were substantial disagreement regarding when disclosure should take place, who should make the disclosure (the patient or the health care professionals), and to whom the results should be disclosed. Patients and family members may hold different attitudes toward CSGT uptake of and disclosure of results within the family. Our findings reinforce the need for a family system approach to incorporate perspectives of patients as well as their family members.

Rupture of an endometrioma with extremely high serum CA-125 level (> 10,000 IU/ml) and ascites resembling ovarian cancer

Carbohydate antigen 125 (CA-125) is a type of cell surface glycoproteins present in more than 80% of non-mucinous epithelial ovarian carcinomas; however, benign gynecologic conditions commonly cause a smaller increase in CA-125 level. This report presents the details regarding a 44-year-old woman with extremely high serum CA-125 level and ascites. She complained of having abdominal pain and abdominal distension. Her serum CA-125 level had been markedly elevated (> 10,000 IU!ml) and computed tomograpgy (CT) revealed an ovarian tumor and massive ascites. The cytological analysis showed no evidence of malignancy, however, the positron emission CT (PET-CT) scan suggested ovarian malignancy with peritoneal carcinomatosis. Under the impression that the patient had ovarian cancer, the present surgical team carried out an explorative laparotomy and discovered the ruptured bilateral ovarian endometriomas. In this study, it is suggested that clinicians carrying out differential diagnosis of pelvic mass with high serum CA-125 level and ascites should consider not only ovarian cancer but also ruptured endometrioma.

The routine value of anogenital distance as an anthropometric measurement in newborns

OBJECTIVE

Anogenital distance (AGD) is a sexually dimorphic trait; AGD is an external marker of sexual differentiation at birth in animals.

STUDY DESIGN

The present study used a prospective, cross-sectional design. Data were collected from newborn infants that were delivered at hospital in Bucheon between March and September 2009. The mothers of the infants provided sociodemographic information and obstetric history. The relationships between AGD and other anthropometric measures (i.e., weight, height, and head circumference) were analyzed. Moreover adjusted AGD values were compared with obstetric characteristics, including number of deliveries, abortion history, preterm history, and duration of gestation.

RESULTS

Significant correlations were noted for all anthropometric measures in male and female newborns (p < 0.0001). The adjusted AGD values in males and females were also significantly associated with the duration of gestation (p = 0.0008 and p = 0.0148, respectively). Moreover, the adjusted AGD in female newborns, but not in males, was significantly associated with maternal abortion history (p = 0.0242).

CONCLUSION

The AGD is a valuable anthropometric marker in term infants.

Abstract P5-08-01: Systematic interrogation of resistance to HER2-directed therapy identifies a survival pathway activated by PRKACA and PIM1

Amplification and/or overexpression of the receptor tyrosine kinase HER2 occurs in 20-25% of breast cancers, and is associated with poor prognosis. Targeting of HER2 with drugs such as trastuzumab, lapatinib, or pertuzumab has led to clinical benefit in patients with both metastatic and early-stage HER2-amplified breast cancer. However, resistance and disease progression always occurs in patients with metastatic disease, and many patients with early-stage breast cancer experience recurrences despite adjuvant anti-HER2 therapy. As such, understanding the mechanisms of resistance to anti-HER2 therapy has important clinical implications.

Recent studies have identified mutations in PIK3CA, the gene encoding the catalytic subunit of Phosphatidylinositol 3 kinase (PI3K), as one mechanism of resistance to trastuzumab. However, such mutations are present in only a fraction of trastuzumab-resistant breast cancers. We therefore sought to uncover novel mechanisms of resistance to anti-HER2 therapy through an unbiased screen for kinases and kinase-related molecules that are able to rescue HER2-amplified breast cancer cells from HER2 inhibition.

We utilized a library of nearly 600 lentivirally-delivered open reading frames (ORFs) to constitutively express the coding sequence of each molecule individually in HER2-amplified BT474 breast cancer cells in arrayed high-throughput format. We conducted two parallel screens for the ability of each of these molecules to rescue cells from anti-HER2 therapy: one in which we treated the cells with a lapatinib-like drug that inhibits the kinase activity of HER2 and EGFR, and one in which we lentivirally delivered a short hairpin RNA that suppresses expression of HER2.

We identified those ORFs that restored viability of BT474 cells to greater than two standard deviations above the median of all ORFs in each screen. Multiple members of the MAPK and PI3K signaling pathways scored in both screens, serving to validate the approach. In addition, the survival kinases PIM1 and PRKACA scored robustly. Mechanistic studies suggest that these kinases may confer resistance by restoring the phosphorylation of, and thereby inactivating, the pro-apoptotic protein BAD. Consistent with this finding, overexpression of Bcl-xl, which is inhibited by BAD, also conferred resistance to lapatinib in HER2-amplified breast cancer cells. Furthermore, pharmacological blockade of Bcl-xl and Bcl-2 with ABT-263 enhanced lapatinib-induced killing of HER2-amplified breast cancer cells in vitro, and partially abrogated the rescue conferred by both PRKACA and PIM1. These findings suggest that combined inhibition of HER2 and the anti-apoptotic molecules Bcl-xl and Bcl-2 could enhance tumor cell eradication and prevent or delay the emergence of resistant disease.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-08-01.

Germline mutations and genotype-phenotype correlations in patients with apparently sporadic pheochromocytoma/paraganglioma in Korea

The aim of our study was to assess the frequency of germline mutations and develop the genetic testing strategy in patients with apparently sporadic pheochromocytoma/paraganglioma (PPGL) in Korea. We included 53 patients diagnosed with non-syndromic PPGL without a family history of PPGLs in three referral centers from 2004 to 2011. Succinate dehydrogenase complex B (SDHB), SDHD, Von Hippel-Lindau (VHL), and rearranged during transfection (RET) genes were examined by direct sequencing and multiple ligation-dependent probe amplification. The study patients were composed of 26 men and 27 women, and mean age was 50.1 ± 13.5 years. The frequency of germline mutations was 13.2% (7/53): RET (n = 2), VHL (n = 1), SDHB (n = 2), and SDHD (n = 2). Six of seven mutation carriers were diagnosed before the age of 50. One of two patients harboring an SDHB mutation had malignant PPGLs. One patient with multifocal head and neck paraganglioma (PGL) and pheochromocytoma (PHEO) carried a SDHD mutation. The carriers of germline mutations in patients with apparently sporadic PPGL were 13.2% in our study. We recommend genetic testing in patients below 50 years and SDHD genetic testing in patients with multifocal PPGLs. In malignant PPGLs, SDHB genetic testing may be performed.

(18)F-FDG PET/CT surveillance at 3-6 and 12 months for detection of recurrence and second primary cancer in patients with head and neck squamous cell carcinoma

Background:

Early detection of recurrence of head and neck squamous cell carcinoma (HNSCC), which is often obscured by surgical or radiotherapy-induced tissue distortion, is essential for proper patient management.

Methods:

A total of 143 consecutive patients with previously untreated HNSCC were evaluated by whole-body fluorine 18-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and regular clinical follow-up after curative treatment. The ¹⁸F-FDG PET/CT was performed ∼3–6 and 12 months after treatment and findings suspicious for recurrence or SPC were confirmed using histopathology.

Results:

The sensitivities of 3–6- and 12-month PET/CT scans at patient level were 96% and 93%, respectively, and those of regular clinical follow-up were 11% and 19%, respectively (McNemar test, P<0.001). In patients with no clinical suspicion, PET/CT detected 95% and 91% of recurrent patients at 3–6 and 12 months, respectively. The sensitivity of PET/CT for the identification of SPC was 29% and 80% at 3–6 and 12 months, respectively. A positive interpretation of PET/CT was significantly associated with poor overall survival (log-rank test, P<0.001).

Conclusion:

The ¹⁸F-FDG PET/CT surveillance is beneficial for the detection of recurrence that may be missed by regular follow-up physical and endoscopic examinations of the head and neck area after curative treatment for HNSCC.

S-1 plus irinotecan and oxaliplatin for the first-line treatment of patients with metastatic colorectal cancer: a prospective phase II study and pharmacogenetic analysis

BACKGROUND

S-1 is an oral fluoropyrimidine that mimics infusional 5-fluorouracil. The aim of this phase II trial was to explore the clinical efficacy of the triplet regimen TIROX, which consists of S-1, irinotecan and oxaliplatin.

METHODS

Forty-two chemo-naive patients with metastatic colorectal cancer (mCRC) were planned to be enrolled and be treated with irinotecan 150 mg m(-2) followed by oxaliplatin 85 mg m(-2) on day 1 and S-1 80 mg m(-2) per day from day 1 to 14 every 3 weeks. Polymorphisms in the UGT1A1, UGT1A6, UGT1A7 and CYP2A6 genes were analysed.

RESULTS

Between July 2007 and February 2008, 43 patients were enrolled. An objective response was noted in 29 patients (67.4%, 95% confidence interval: 53.4-81.4), of which 2 achieved durable complete responses. The median progression-free survival was 10.0 months and the median overall survival was 19.2 months. Significant grade 3 or 4 adverse events were neutropenia (45.2%), febrile neutropenia (9.5%), diarrhoea (7.1%) and vomiting (9.5%). Increased gastrointestinal toxicities were associated with the presence of UGT1A6*2 or UGT1A7*3 and an improved tumour response was noted in those without variant alleles of CYP2A6 or UGT1A1*60.

CONCLUSION

The combination of S-1, irinotecan and oxaliplatin showed favourable efficacy and tolerability in untreated patients with mCRC.

Utility of quantitative 18 F-fluorodeoxyglucose uptake measurement to identify occult tonsillar carcinoma in patients with cervical metastasis of unknown primary tumours: a retrospective case-control study

OBJECTIVES

Due to relatively high (18) F-fluorodeoxyglucose accumulation in the tonsillar region, the detection of occult tonsillar cancers by (18) F-fluorodeoxyglucose positron emission tomography/computerised tomography remains controversial. Therefore, we assessed the usefulness of quantitative tonsil (18) F-fluorodeoxyglucose uptake in identifying occult tonsillar squamous cell carcinoma.

DESIGN

A case-control study of retrospective cohorts.

SETTING

University Teaching Hospital.

MAIN OUTCOME MEASURES

We assessed all patients diagnosed with tonsillar cancers or cervical lymph node metastasis of unknown primary tumours between 2005 and 2010 who underwent (18) F-fluorodeoxyglucose positron emission tomography/computerised tomography. The subjects were grouped into A (apparent early pT-stage tonsillar squamous cell carcinoma; n = 27), B (occult tonsillar squamous cell carcinoma, primary tumours were found by surgery; n = 21), C (cervical metastasis of unknown primary tumour, primary tumours were not found by surgery and for follow-up; n = 16) and D (33 healthy controls). Tonsillar maximum standardised uptake values were bilaterally measured and compared between groups.

RESULTS

The sensitivity and specificity of qualitative assessment of (18) F-fluorodeoxyglucose positron emission tomography/computerised tomography for detection of occult tonsillar cancers were 67% and 69%, respectively. Mean maximum standardised uptake values of tonsils with cancer were 11.19 ± 5.46 in group A and 8.12 ± 4.52 in group B, which were significantly higher than that of group C (4.62 ± 1.76) or group D (4.57 ± 1.62) (P < 0.01). The mean maximum standardised uptake value differences of groups A (6.35) and B (3.11) were significantly greater than those of groups C (0.32) and D (0.59) (P < 0.01). Similarly, the mean maximum standardised uptake value ratios of groups A (2.47) and B (1.73) were significantly greater than those of groups C (1.06) and D (1.16) (P < 0.01).

CONCLUSION

(18) F-fluorodeoxyglucose positron emission tomography/computerised tomography with tonsil SUVmax measurement is useful to identify occult tonsillar squamous cell carcinoma.

Second-line chemotherapy versus supportive cancer treatment in advanced gastric cancer: a meta-analysis

BACKGROUND

Many patients with refractory or relapsed gastric cancer after first-line chemotherapy have received salvage chemotherapy in routine clinical practice. However, there was no evidence to support this treatment until recent phase III trials demonstrated substantial prolongation of overall survival. Therefore, we conducted a meta-analysis of these trials and investigated whether second-line chemotherapy was more effective than best supportive care.

PATIENTS AND METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 1, 2013), MEDLINE (1950 to March week 4, 2013) and EMBASE (1980-2013, week 13). In addition, we searched all abstracts and virtual meeting presentations from the American Society of Clinical Oncology (ASCO) conferences held between 2004 and 2013.

RESULTS

The search process yielded 578 studies, two of which were randomized phase III trials that compared chemotherapy with supportive care. From the abstracts and virtual meeting presentations of ASCO held between 2004 and 2013, 127 abstracts were identified that evaluated second-line chemotherapy; only one relevant abstract was included in the meta-analysis. A total of 410 patients were eligible for analysis, of whom 150 received docetaxel chemotherapy, and 81 received irinotecan chemotherapy. A significant reduction in the risk of death [HR = 0.64, 95% confidence interval (CI) 0.52-0.79, P < 0.0001] was observed with salvage chemotherapy. When the analysis was restricted to irinotecan or docetaxel, there was still significant reduction in the risk of death with each chemotherapeutic agent. The HR was 0.55 (95% CI 0.40-0.77, P = 0.0004) for irinotecan and 0.71 (95% CI 0.56-0.90, P = 0.004) for docetaxel.

CONCLUSION

This meta-analysis demonstrated evidence to support second-line chemotherapy in advanced gastric cancer.

Discovery of Q203, a potent clinical candidate for the treatment of tuberculosis

New therapeutic strategies are needed to combat the tuberculosis pandemic and the spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of the disease, which remain a serious public health challenge worldwide. The most urgent clinical need is to discover potent agents capable of reducing the duration of MDR and XDR tuberculosis therapy with a success rate comparable to that of current therapies for drug-susceptible tuberculosis. The last decade has seen the discovery of new agent classes for the management of tuberculosis, several of which are currently in clinical trials. However, given the high attrition rate of drug candidates during clinical development and the emergence of drug resistance, the discovery of additional clinical candidates is clearly needed. Here, we report on a promising class of imidazopyridine amide (IPA) compounds that block Mycobacterium tuberculosis growth by targeting the respiratory cytochrome bc1 complex. The optimized IPA compound Q203 inhibited the growth of MDR and XDR M. tuberculosis clinical isolates in culture broth medium in the low nanomolar range and was efficacious in a mouse model of tuberculosis at a dose less than 1 mg per kg body weight, which highlights the potency of this compound. In addition, Q203 displays pharmacokinetic and safety profiles compatible with once-daily dosing. Together, our data indicate that Q203 is a promising new clinical candidate for the treatment of tuberculosis.

The evaluation of dentinal tubule occlusion by desensitizing agents: a real-time measurement of dentinal fluid flow rate and scanning electron microscopy

The aims of this study were to examine changes in dentinal fluid flow (DFF) during the application of a desensitizing agent and to compare the permeability reduction levels among different types of desensitizing agents. A cervical cavity was prepared for the exposure of cervical dentin on an extracted human premolar connected to a subnanoliter fluid flow measuring device under 20 cm of water pressure. The cavity was acid-etched with 32% phosphoric acid to make dentin highly permeable. The different types of desensitizing agents that were applied on the cavity were Seal&Protect as the light-curing adhesive type, SuperSeal and BisBlock as oxalate types, Gluma Desensitizer as the protein-precipitation type, and Bi-Fluoride 12 as the fluoride type. DFF was measured from the time before the application of the desensitizing agent throughout the application procedure to five minutes after the application. The characteristics of dentinal tubule occlusion of each desensitizing agent were examined by scanning electron microscopy. The DFF rate after each desensitizing agent application was significantly reduced when compared to the initial DFF rate before application for all of the desensitizing agents (p<0.05). Seal&Protect showed a greater reduction in the DFF rate when compared to Gluma Desensitizer and Bi-Fluoride 12 (p<0.05). SuperSeal and BisBlock exhibited a greater reduction in DFF rate when compared to Bi-Fluoride 12 (p<0.05). The dentin hypersensitivity treatment effects of the employed desensitizing agents in this study were confirmed through real-time measurements of DFF changes. The light-curing adhesive and oxalate types showed greater reduction in the DFF rate than did the protein-precipitation and fluoride types.

Expression of exogenous LIN28 contributes to proliferation and survival of mouse primary cortical neurons in vitro

LIN28, an RNA-binding protein, is known to be involved in the regulation of many cellular processes, such as embryonic stem cell proliferation, cell fate succession, developmental timing, and oncogenesis. In this study, we investigated the effect of constitutively expressing exogenous LIN28 on neuronal cell proliferation and viability in vitro. Plasmids containing LIN28-green fluorescent protein (GFP) or GFP were introduced into the embryonic mouse brains at E14.5 by in utero electroporation. Two days after electroporation, embryonic cortices were harvested and cultured. It was found that transfected cells stably overexpressed LIN28 in vitro. Viability curve from live cell imaging showed that the number of GFP-expressing cells decreased over time in line with naive primary cortical neurons. In contrast, the number of LIN28-GFP-overexpressing neurons initially increased and remained high at later time-points in culture than GFP-expressing cells. Double immunofluorescence showed that at an early time in culture, the number of Ki-67/GFP double-positive cells was higher in the LIN28-GFP group than that of controls. Moreover, there were significantly lower numbers of condensed nuclei/GFP- and cleaved caspase-3/GFP-positive cells in the LIN28-GFP groups compared to control GFP. Furthermore, it was confirmed that the LIN28-GFP-expressing cells at days in vitro (DIV)13 were neuronal nuclei (NeuN)-positive mature neurons. Finally, the expression of insulin-like growth factor 2 (IGF-2) was induced in LIN28-expressing primary cortical neurons, which was not detected in controls. Taken together, our results indicate that the expression of exogenous LIN28 can promote the proliferation of neural progenitor cells and exert prosurvival effect on primary cortical neurons by inhibiting caspase-dependent apoptosis, possibly via upregulation of IGF-2.

Refactoring redox cofactor regeneration for high-yield biocatalysis of glucose to butyric acid in Escherichia coli

In this study, the native redox cofactor regeneration system in Escherichia coli was engineered for the production of butyric acid. The synthetic butyrate pathway, which regenerates NAD(+) from NADH using butyrate as the only final electron acceptor, enabled high-yield production of butyric acid from glucose (83.4% of the molar theoretical yield). The high selectivity for butyrate, with a butyrate/acetate ratio of 41, suggests dramatically improved industrial potential for the production of butyric acid from nonnative hosts compared to the native producers (Clostridium species). Furthermore, this strategy could be broadly utilized for the production of various other useful chemicals in the fields of metabolic engineering and synthetic biology.

Fiber type composition of the architecturally distinct regions of human supraspinatus muscle: a cadaveric study

The human supraspinatus muscle is clinically important as it is frequently injured in older adults and the elderly. We have previously shown that the supraspinatus has a complex architecture with two distinct regions each consisting of three parts. Further we have found dynamic changes in architectural parameters such as fiber bundle length markedly vary between these regions. Fiber types of the supraspinatus have not been thoroughly investigated throughout its volume and are of interest to clinicians treating supraspinatus pathologies. In this study we investigated the distribution of fiber types within the distinct regions and parts of supraspinatus. Samples of supraspinatus were excised from six distinct parts of each muscle from five formalin embalmed specimens (one male, four female; mean age 77±11.1 years) free of tendon pathology. Samples were frozen in liquid nitrogen and then cryosectioned. Serial sections were labeled using immunohistochemical techniques and antibodies against fast or slow myosin heavy chain isoforms. The mean percentage of Type I (slow) fibers ranged from 56.73% to 63.97%. Results demonstrated significant variations in fiber type distribution. The middle part of the anterior region has a significantly greater percentage of Type I fibers compared to that of the posterior. The superficial part of the anterior region has a greater percentage of Type II (fast) fibers compared to the middle and deep parts. Findings aid in highlighting the distinct functions of the anterior and posterior regions, and prompt the need to re-evaluate assessment and treatment techniques established on a limited understanding of the fiber type distribution.